Gaseous electric discharge device



July 23, 1935. K. wlEGAND GASEOUS ELECTRIC DISCHARGE DEVICE Filed March 18, 1955 'IIIIIIIIIIIIIIIII /l 'LLL/4444. lll/II INVENTOR Tl l ORNEY Patented July 23, 1935 UNITED STATES PATENT OFFICE GASEOUS ELECTRIC DISCHARGE DEVICE Application March 18, 1935, Serial No. 11,699 In Germany March 19, 1934 2 Claims.

The present invention relates to gaseous electric discharge devices and more particularly the invention relates to protective means for the current leads of high voltage gaseous electric disl charge devices, such as luminous tubes useful in advertising.

It is an excellent practice to surround the current leads of such devices with a grounded metallic sheath. It is desirable to have a flexible sheath. Lead and aluminium sheaths, the latter type having corrugations in the walls thereof to make them flexible are useful in this connection. Current leads sheathed in this manner have a higher capacity than leads having no metal sheath and this capacity in leads y20 meters in length and longer tends to eliminate the inductive voltage drop of the choke coil or of the leaky transformer in the circuit. The tubes in such a` circuit flicker badly. Hitherto this capacitive action of the metal sheathed leads has been thought of as a disadvantage in such circuits and the elimination or the reduction of this capacitive effect of the current leads has been attempted by using short leads or by connecting a compensating resistance, such as an ohmic resistance or a choke coil, into the circuit between the luminous tubes and the high voltage side of the transformer therefor.

The object of the present invention is to provide a circuit for luminous tubes, or similar high voltage devices, in which the capacitive effect of metal sheathed current leads is utilized in the operation of such devices. Still further objects and advantages attaching to the device and to its use and operation will be apparent to those skilled in theart from the following particular description.

In accordance with these objects the invention comprises a luminous tube and a high voltage transformer. One electrode of the tube is connected directly to one terminal of the high voltage vside of the transformer and the other electrode thereof is connected to the other terminal of the transformer through a current lead having an 45 insulating coating covered by a metallic sheath which sheath is connected to said transformer terminal. This latter terminal of the high voltage transformer is grounded and one end of the current lead connected thereto is connected to the electrode of the tube while the other end thereof is oatlng. This current lead is thus a capacitative external resistance for the luminous tube 'and special, compensating resistances connected into the primary or the secondary side of the and novel apparatus comprises a luminous tube I 15 consisting of an elongated glass container having electrodes 5 and I0 sealed into the ends thereof and having an electric discharge conducting gaseous atmosphere therein, such as neon. The apparatus also comprisesl a transformer having a 20 primary coil 2 and a secondary coil 3. The terminals 2', 2" o f the primary coil are connected to an alternating current source of commercial voltage, such as 220 volts. The terminal 3' of the secondary coil 3 is connected with the elec- 25 trode 5 of the luminous tube I by the current lead 4 provided with the customary insulation. The terminal 3" of the tube transformer is grounded by the lead 6 and is connected with the metallic protective sheath 8 of the current 3o lead 9 by the current lead l. One end of said lead 9 is dead and the other end thereof is connected to the electrode I0 of the tube I. The insulation II between the metallic protective sheath 8 and the lead 9 here forms the dielectric 35 of a condenser the metallic layers of which consist of the metallic protective sheath 8 and the lead 9. The metallic protective sheath 8 is coated with a protective layer of a suitable insulating material, when desired.

A plurality of luminous tubes connected in series are used in the above described circuit, when desired. When a plurality of luminous tubes connected in parallel are desired the circuit illustrated in Fig. 2 is effective. The circuit illus- 45 trated in Fig. 2 of the drawing comprises a plurality of luminous tubes I similar to that described in connection With Fig. 1. The electrode 5 of each of the tubes I is connected to a common lead 4 by the lead I2. The common lead 4 50 is connected to the terminal 3 of thesecondary coil 3 of the transformer. The terminal 3 of the transformer is again connected to ground by lead 6 and to the protective sheath 8 of a. high voltage cable by the lead 1. 'I'he high voltage 55 cable comprises ve leads 9 each of which is connected at one end thereof, to an electrode I0 of one of the tubes l. 'I'he other end of said leads 9, as in the circuit of Fig. 1, comes to a dead end. The greater part of said common lead l is also surrounded by the metallic protective sheath 8. The operation of this circuitl is substantially the same as that illustrated in Fig. l of the drawing.

When desired, the lead 4 is not surrounded by said sheath B. 'I'he capacity of the condenser consisting of the enclosed leads l and 9, the protective sheath 8 and the insulation Il is determined by the dielectric material, that is, the insulating material Il and the capacity desired can be obtained by selecting the proper dielectric material. Since the enclosed conductors influence each other reciprocally, the capacity in the arrangement according to Fig. 2, is still further increased.

What I claim as new and desire to secure by Letters Patent of the United States is:-

1. A circuit comprising in combination a gaseous electric discharge device, a current source therefor, and current leads therefor, one terminal of said current source being grounded, one of said current leads connecting a terminal of said device to a terminal of said current source other than said grounded terminal. another of said current leads connecting another terminal oi.' said device to said grounded terminal, said last named current lead being a capacitative resistance i'or said device and comprising a conducting wire, a tube of insulating material surrounding said wire and a sheath of conducting material for said insulating material, one end of said wire being connected to a terminal of said device, said sheath being connected to the grounded terminal of said current source.

2. A circuit comprising in combination a plurality of gaseous electric discharge devices connected in parallel, a current source therefor, and current leads therefor, one terminal of said current source being grounded, one terminal of each of said devices being connected to a terminal of said current source other than said grounded terminal through a common conductor, the other terminal of each of said devices having a wire of conducting material connected thereto. said conducting wires being covered with insulating material and a sheath of conducting material surrounding said insulated wires and said common conductor, said sheath being connected to the grounded terminal of said current source, said sheath and said wires being a capacitative resistance for said device. l

KURT WIEGAND. 

